Site is very easy to navigate and steps to order flow quickly and simply. This is the third K&N filter I have ordered and like the rest it arrived before I expected and was in perfect new shape. I installed this one on the 2007 Honda S2000 and have not taken any measurements yet, but it does seem to have improved low rpm performance. The other 2 on are my '71 Fiat 124 Spider (Dual Webers) and 2012 Infinity M37. I generally keep our main car for 5 to 7 years, and sport cars for 10 to 15 (except Fiat which I have had since 1977). So lifetime filters are the only way for me to go even if there was no performance improvement.